20406681600 has 180 divisors, whose sum is σ = 67480097664. Its totient is φ = 5441454080.

The previous prime is 20406681577. The next prime is 20406681611. The reversal of 20406681600 is 618660402.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1220497 + ... + 1237103.

Almost surely, 2^20406681600 is an apocalyptic number.

20406681600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20406681600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33740048832).

20406681600 is an abundant number, since it is smaller than the sum of its proper divisors (47073416064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20406681600 is an equidigital number, since it uses as much as digits as its factorization.

20406681600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16648 (or 16617 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The spelling of 20406681600 in words is "twenty billion, four hundred six million, six hundred eighty-one thousand, six hundred".